خيارات البحث
النتائج 191 - 200 من 572
Identification and partial sequencing of a crocodile poxvirus associated with deeply penetrating skin lesions in farmed Nile crocodiles, <i>Crocodylus niloticus</i>
2009
F.W. Huchzermeyer | D.B. Wallace | J.F. Putterill | G.H. Gerdes
When large numbers of crocodile skins were downgraded because of the presence of small pin pricklike holes, collapsed epidermal cysts were found deep in the dermis of juvenile crocodiles while forming cysts were observed in hatchlings. Histopathology of these forming cysts showed the presence of intracytoplasmic inclusions in proliferating and ballooning epidermal cells. Pox virions were seen in electron microscope preparations made from the scabs of such early lesions. The partial sequencing of virus material from scrapings of these lesions and comparison of it with the published sequence of crocodile poxvirus showed the virus associated with the deep lesions to be closely related, but different. To differentiate between the two forms of crocodile pox infection it is suggested that the previously known form should be called ''classical crocodile pox'' and the newly discovered form ''atypical crocodile pox''. The application of strict hygiene measures brought about a decline in the percentage of downgraded skins.
اظهر المزيد [+] اقل [-]Strain differences of cerebral ventricles in mice: Can the MRL/MpJ mouse be a model for hydrocephalus?
2009
Hino, K.(Hokkaido Univ., Sapporo (Japan)) | Otsuka, S. | Ichii, O. | Hashimoto, Y. | Kon, Y.
Hydrocephalus is an intractable disease characterized by the excessive accumulation of cerebrospinal fluid (CSF) in the cerebral ventricles. There are many cases in both human and animals; however, the cause and mechanism of its development is not clearly understood. In this study, differences of cerebral ventricles in 5 inbred mice strains (MRL/MpJ, C57BL/6, C3H/He, DBA/2 and BALB/c) were investigated by histological techniques to determine the possibility of a new animal model for hydrocephalus. Our analysis showed that significant differences in the volume and the surface area of lateral ventricles in the 5 inbred strains, with MRL/MpJ mice having the largest lateral, third, aqueduct and fourth ventricles. In addition, when MRL/MpJ mice were compared to BALB/c mice on 0 day after birth, the former already had larger lateral ventricles than the latter. Although there was no significant difference in the ratios of ependymal cell types in MRL/MpJ mice and BALB/c mice, the number and the diameter of lipid droplets in MRL/MpJ mice were, interestingly, smaller than those in BALB/c mice. It is well known that ependymal cells absorb nutritional substances in CSF by endocytosis, suggesting the possibility that their decrease may relate to the larger cerebral ventricles in MRL/MpJ. In conclusion, MRL/ MpJ mice have greater volumes in cerebral ventricles than other strains and may be useful for a model showing high susceptibility to hydrocephalus.
اظهر المزيد [+] اقل [-]Change in body weight of mothers and neonates and in milk composition during denning period in captive Japanese black bears (Ursus thibetanus japonicus)
2009
Iibuchi, R.(Hokkaido Univ., Sapporo (Japan)) | Nakano, N. | Nakamura, T. | Urashima, T. | Shimozuru, M. | Murase, T. | Tsubota, T.
Japanese black bears, Ursus thibetanus japonicus, have been classified as a vulnerable species so that data on reproduction are needed to maintain and/or extend their population. They are known to have a peculiar style of reproduction, giving birth to their neonates and raising them during denning, a period of complete fasting. In this study, we investigated the metabolic rate and milk composition of mother bears raising neonates, and the changes in body weight of the neonates under captive conditions. Seven female bears kept in dens were weighed once a month, and the amount of energy they used was calculated. From birth, cubs were also weighed and their growth rate was determined. In addition, the milk composition was analyzed to investigate its characteristics. As a result, it was found that mother bears used 34% more energy than did solitary females. There was no significant difference in the energy used for nursing whether they had single or twin cubs. On the other hand, the body weight gain of single cubs was significantly higher than that of twin cubs, suggesting that the growth of the cubs was highly affected by the suppression of mother's energy consumption during the fasting period. The milk had high fat and low sugar concentrations. This indicates that mother bears used the fat accumulated prior to denning for their main energy source when raising cubs. Considering all results together, Japanese black bears showed remarkable efficiency in the use of energy for reproduction during the fasting period.
اظهر المزيد [+] اقل [-]Preliminary studies on the effects of orally-administered transforming growth factor-beta on protozoan diseases in mice
2009
Namangala, B.(Obihiro Univ. of Agriculture and Veterinary Medicine, Hokkaido (Japan)) | Inoue, N. | Sugimoto, C.
Transforming growth factor beta-1 (TGF-beta1) is a pleiotropic cytokine with both pro- and antiinflammatory properties, depending on its environment and concentration. The present study evaluated the effects of orally-delivered TGF-beta1 on mice parenterally-infected with various protozoan parasites. We report that while orally-administered TGF-beta1 seems to confer partial protection against murine chronic babesiosis and acute trypanosomosis, no beneficial clinical effects were observed against acute babesiosis, malaria or toxoplasmosis. Taken together, these preliminary data suggest that the systemic effects conferred by exogenous TGF-beta1 could be parasite species-specific. The variations in different parasitic infections could be due to (i) intrinsic differences between parasite species and/or strains in their ability to induce production of immunosuppressive molecules and/or (ii) differences in mechanisms governing host protection against different parasitic infections.
اظهر المزيد [+] اقل [-]Protective effect of Pleurotus cornucopiae mushroom extract on carbon tetrachloride-induced hepatotoxicity
2009
Bohi, K.M.E.(Zagazig Univ., Kaluobyia (Egypt)) | Hashimoto, Y. | Muzandu, K. | Ikenaka, Y. | Ibrahim , Z.S. | Kazusaka, A. | Fujita, S. | Ishizuka, M.
Pleurotus cornucopiae (PC) mushrooms are found in the field and commonly known in Japan as Tamogidake mushrooms. The present study investigated the protective effects of an aqueous extract of PC on carbon tetrachloride (CCl4)-induced hepatotoxicity and the possible mechanism involved in this protection including cytochrome P450 (CYP) 2E1. Wistar rats were pretreated with aqueous extracts of PC (0, 100, 200, and 400 mg/kg) orally for 8 days prior to the intraperitoneal administration of a single dose of CCl4 (0.5 ml/kg) or corn oil. Pretreatment with PC mushroom extract significantly prevented the increased serum enzyme activities of alanine and aspartate aminotransferases in a dose-dependent manner, and suppressed the expression of CYP2E1. PC mushroom extract also protected hepatocytes from the damage effects of CCl4 as remarked by histological and electromicroscopical findings. It was concluded that repeated daily doses of aqueous extracts of PC mushroom reduced the toxic effects exerted by CCl4 on the liver.
اظهر المزيد [+] اقل [-]Structural implications of the EL(K/Q)(L/C)LD(A/G)DD sequence in the C-terminal cytoplasmic tail for proper targeting of anion exchanger 1 to the plasma membrane
2009
Adachi, H., Hokkaido Univ., Sapporo (Japan) | Ito, D. | Kurooka, T. | Otsuka, Y. | Arashiki, N. | Sato, K. | Inaba, M.
While the C-terminal cytoplasmic tail of anion exchanger 1 (AE1, band 3) has been reported to possess important physiological roles, including one for proper membrane trafficking, its precise characteristics remain unclear. To clarify the overall structural consequences of the conserved sequence EL(K/Q)(L/C)LD(A/G)DD, containing the core binding sequence LDADD for carbonic anhydrase II, in the C-terminal region, we analyzed the membrane expression and turnover of bovine AE1 with a series of truncation and substitution mutations in HEK293 cells. Immunofluorescence microscopy and cell-surface biotinylation demonstrated that truncation mutants missing 18 C-terminal residues targeted the plasma membrane, but the one lacking the conserved region, by truncation of 28 amino acid residues, was retained inside the cells. Substitutions of Ala for Glusup(901), Leusup(902), Leusup(905), and Aspsup(906) in the sequence E901L(K/Q)(L/C)LDADD909 of bovine AE1 or those in the corresponding murine sequence also caused intracellular retention, though these mutants had half-lives comparable to that for wild-type AE1. These data demonstrate that the conserved amino acid residues Glusup(1), Leusup(2), Leusup(5), and Aspsup(6) in the EL(K/Q)(L/C)LD(A/G)DD region have essential structural consequences in stable expression of AE1 at the plasma membrane regardless of the ability in binding to carbonic anhydrase II of this region.
اظهر المزيد [+] اقل [-]Growth variation in skull morphology of Kuril harbor seals (Phoca vitulina stejnegeri) and spotted seals (Phoca largha) in Hokkaido, Japan
2009
Nakagawa, E., Hokkaido Univ., Sapporo (Japan) | Kobayashi, M. | Suzuki, M. | Tsubota, T.
We examined morphological growth variations in skull features between the Kuril harbor seal and the spotted seal in Hokkaido, Japan. Skulls from 80 Kuril harbor seals and 41 spotted seals were collected, and we measured 29 metric and 6 non-metric cranial characteristics. Three growth classes were defined according to the postnatal developmental stage: pups (0 year), subadults (1-4 years old) and adults (more than 5 years old). We detected sexual dimorphism in Kuril harbor seal pups, subadults, and adults. Although interspecies differences were detected in each growth class, Kuril harbor seals were larger and more massive than spotted seals; this feature was already detectable in pups. We did not detect certain cranial characteristics with which to identify the two species, but it was possible to identify any unknown specimens to their species, sex, and growth class using the cranial data generated in this study. Using 6 non-metric cranial characteristics, we identified significant interspecies differences with regard to the shape of the temporozygomatic suture and the extent of the nasal-incisive suture; the shape of the temporozygomatic suture and the shape of the nares were indicators of growth class in Kuril harbor seals. Although non-metric cranial characteristics have a lower discriminating power than metric characteristics, they are easy to use in the field even by inexperienced researchers.
اظهر المزيد [+] اقل [-]Radioecological investigation of food of animal origin in Belgrade environment
2009
Gordana, V., Belgrade Univ. (Serbia) | Svetlana, G. | Branislava, M. | Milan, O. | Branko, P.
The activity concentrations of sup(40)K, sup(238)U, sup(232)Th and sup(137)Cs were measured using gamma spectrometric method in different food chain samples from Serb Belgrade environment during the periods May-June 2007 and May-June 2008 year. Relatively high activities of sup(40)K and sup(137)Cs were detected in the soil. These results indicate that sup(137)Cs is present in Belgrade environment even 20 years after nuclear accident in Chernobyl. However, in the samples of feedstuffs, animal products and bio indicators (meat of wild animals and fish), activity concentrations of primordial radionuclides and sup(137)Cs were low and below the detection limits. Results of these trials have shown that investigated animal products from the natural environment around Belgrade, are radioactivity safe.
اظهر المزيد [+] اقل [-]Prevalence of True Anoestrus and Delayed Puberty in Cattle.
2009
Bhattacharyya, H. K. | Makhdoomi, D. M. | Hafiz, A.
An overall prevalence of 20.07% true anoestrus and delayed puberty in cattle was recorded out of 2202 gynaecological cases presented to the clinical complex and different clinical camps held at different locations of Kashmir valley over a period of three years (2005_2008). The highest prevalence of true anoestrus in cows was recorded in the 1st parity when they attained approximately 3 years of age and during autumn season.
اظهر المزيد [+] اقل [-]Clinical and Biochemical Alterations Following Epidural Administration of Bupivacaine, Bupivacaine + Hyaluronidase and Hyperbaric Bupivacaine in Dogs.
2009
Murmu, S. | Dass, L.L. | Sharma, A.K.
The study was conducted in 18 clinically healthy male dogs of about 1 year of age, weighing up to 12 kg and divided into three groups of 6 animals each. Bupivacaine alone, bupivacaine + hyaluronidase and hyperbaric bupivacaine were given epidurally at lumbosacral space @2 mg/kg. bwt. with a maximum dose of 3 ml in the animals of groups I, II and III, respectively. A significant increase (P0.01) in rectal temperature, heart rate and respiration rate was recorded at initial intervals of observation in all the groups and thereafter these values follow a declining trend in all groups consistently and reached to almost base line value at 120 min. of observation The alterations of glucose, serum urea nitrogen, aspartate aminotransferase and creatinine estimated at 1hr, 2hrs, 4hrs and 24 hrs were remained within physiological limits in all the groups.Therefore induction of regional anaesthesia with bupivacaine and its combination revealed no permanent alteration in the biochemical and physiological parameters hence it is safe and satisfactory anaesthesia.
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